- By default, qmail tries for a week to deliver a message before it
gives up. No warning whatsoever is sent to the sender before. Is
there no way to make it send a delay warning after 4 hours?

- The failure notices include the original mail as unformatted
plaintext. Why doesn't it include it as a MIME entity (or as multiple
entities) so that the user receiving the notice can easily reuse the
contents to send the message again? (i.e. in qmails default way,
attachments are only seen as base64 encoded text, non-ascii chars are
mangled)

- I want to set up a custom failure. For example, "Sorry, there are
several users with this first name on this domain, please use one of
the following full addresses instead: .....". This should really be
a delivery failure message, not an autoreply, and it can be achieved
by putting a program into the dot.qmail file that exits with error
100:

#!/usr/bin/perl
my $txt=<<'END';
Sorry, there are several users with this first name on
this domain, please use one of the following full addresses
instead: .....
END
$txt=~ tr/\n/\r\n/sg;
print $txt;
exit 100;

*BUT* this still gives this ugly, non structured failure notice as
described above, in particular, if I print german umlauts from the
script, they are not sent correctly.

(There is a program "bouncesaying" which has exactly the same drawbacks)
Is there any addon/patch for customizing qmail's automatic messages?
Christian.